Passive entry systems include a portable remote control and a base station. The remote control is carried by a user. The base station is at a target such as a vehicle. The remote control and the base station wirelessly communicate with one another for remotely controlling the vehicle.
Passive entry functions provided by a vehicular passive entry system include automatically unlocking vehicle doors when the remote control (which will be assumed to be authorized for discussion purposes) is detected near the vehicle.
The location of the remote control relative to the vehicle should be detected as the user in possession of the remote control can unlock the vehicle by simply manipulating the door handle. The remote control should be in proximity to the vehicle before unlocking the vehicle. Otherwise, unauthorized users may be able to unlock the vehicle whenever the remote control is within the general vicinity of the vehicle.
Traditionally, the portable remote control was in the form of a key fob. Smartphones, and other wearable devices such as smart watches, are increasingly being provided with key fob functionality and are thereby taking the place of key fobs.